HEIDENHAIN ITNC 530 - 6-2010 DIN-ISO PROGRAMMING User Manual page 185

Entering radius compensation
Radius compensation is entered in a G01 block:
To select tool movement to the left of the
programmed contour, select function G41, or
To select tool movement to the right of the contour,
select function G42, or
To select tool movement without radius
compensation or to cancel radius compensation,
select function G40
To terminate the block, press the END key.
HEIDENHAIN iTNC 530 185